Surf board having a viewing window



FIG. 1 is a top plan view of a surf board having a viewing window showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a front elevational view thereof; and,

FIG. 4 is a rear elevational view thereof. 

The ornamental design for a surf board having a viewing window, as shown and described. 